232 



The Biochemistry of Semen 



Leucine, in semen, 84, 113; in 

 herring testes, 113; in diluents, 

 114 



Light effects, 66-7, 91, 114 



Light-reflection power of sperm, 8, 

 41 



Limpet, nucleic acid, 104 



Lipid, 124-33; redistribution dur- 

 ing spermatogenesis, 6; in semen, 

 32-3, 129-33; in sperm, 6, 86, 

 124-7; in seminal plasma and 

 accessory secretions, 130-3; meta- 

 bolism, 49, 128-30, 172 



Lipid 'bodies', in semen, 131-2 



Lipid capsule, 6, 126; and deter- 

 gents, 57; and senescence, 77, 83 



Lipoprotein, in sperm, 15, 125-6; 

 loss due to damage and senes- 

 cence, 77, 83, 84 



Lipositol, in L. G. B.-pabulum, 81; 

 relation to inositol, 192 



Liquefaction, of semen, 28-9, 114; 

 relation to citric acid, 188 



Lithobius forficatus, cytoplasmic 

 lipids and steroids, 6 



Live-dead (differential) staining, 

 39, 60, 63 



Locusta migratoria (grasshopper), 

 fructose in reproductive organs, 

 136 



Longevity of sperm {see also 

 survival), 9 



Lotahistone, 108 



Luminosity of sperm, 8, 41 



Lump-sucicer, cyclopterin, 106 



Lysine, in seminal proteins, 84, 108; 

 free in human semen, 113; in 

 herring testes, 113; in diluents, 114 



Lytechinus, dilution effect and 

 amino acids, 76; sperm nucleic 

 acid, 104 



Lytic agents, 92-8; relation to 

 fertilization, 95-6 



Mackerel, scombrine, 106; scom- 

 bron, 109 



Magnesium, in semen, 32-3; in 

 prostatic calculi, 132; relation to 

 motility, and metabolism, 77; 

 effect on phosphatases, 121, 123 



Male accessory organs, see acces- 

 sory organs 



Maleic acid, and chemotaxis in 

 plants, 72 



Male sex hormone, see androgens, 

 and testosterone 



Malic acid, role in chemotaxis, 71 



Malnutrition, effect on accessory 

 organs and semen, 148-9 



Malonic acid, effect on sperm, 52 



Man, prostate, 16, 19, 181-88 



Man, prostatic secretion, physico- 

 chemical properties, 17-18; con- 

 tribution to semen, 35; enzymes, 

 17, 114-15, 118-19, 170-1; elec- 

 trolytes, 17-18; protein, 19; lipids 

 and lipid bodies, 130-2; choles- 

 terol, 130; spermine, 166-7; citric 

 acid, 18, 183-8; zinc, 19 



Man, semen, volume and density, 

 2; sperm structure, 11, 14-15; 

 physico-chemical properties, 8, 

 41-5, 60; composition, 32-3; 

 fractions, 35; mineral constitu- 

 tents, 18-19, 32-3, 89, 188; zinc 

 and carbonic anhydrase, 19, 89; 

 reducing substances and ascorbic 

 acid, 33, 48, 179; fructose and 

 fructolysis, 32-4, 48, 136, 147- 

 48; coagulation and liquefaction, 

 28, 188; proteins and proteose in 

 seminal plasma, 111-12; mucoid 

 substance, 112; amino acids, 

 111-13; spermine, and spermi- 

 dine, 160-8; choline and phos- 

 phorylcholine, 130, 168-73; adren- 

 aline, 181; sulphur and gluta- 

 thione, 33; lipids and lipid bodies, 

 101, 126, 130-2; cholesterol, 130; 

 oestrogen and androgen content, 

 68-9; heptacosane and fatty 

 acids, 127-8; citric acid, 17, 



